| 摘要 |
<p>TITLE OF INVENTION Improvements relating to Excavators This invention relates to a mechanical excavator comprising a support part, a boom mounted on the support part for rotation about a horizontal axis, a dipper arm pivotally connected to the boom at the other end thereof, an excavating tool means carrying the excavating tool at one end of the dipper arm, fluid pressure means to cause pivotal movement of the boom relative to the support part and of the dipper arm relative to the boom, the boom comprising a base part pivotally mounted about a first axis to the support part to provide said pivotal connection of the boom and a beam part having the dipper arm pivotally connected thereto about a second axis to provide said pivotal connection of the dipper arm to the boom, bearing means to connect together the base and beam parts said bearing means comprising a pair of parallel channel section guide means, spaced apart transversely of the direction of relative movement between the boom parts, provided on one boom part and having slidably engaged therein opposed flange parts of the other boom part which permit of relative sliding movement between said parts to vary the distance between said first and second axes and clamping means comprising at least one wedge member adapted to be moved into wedging engagement between the boom parts.</p> |
